NASA has named low-cost missions to Venus, the moon and an asteroid on a shortlist to become its latest space adventure, as the US agency faces astronomical political pressure to cut costs.
The proposed probes -- to the surface of Venus, the moon and to bring back a piece of a primitive asteroid -- must all come with a price tag of less than 650 million dollars, a fraction of the cost of manned space flight.
The agency, in a statement Tuesday, said the winner of the competition will be announced in mid-2011, with the project to launch by the end of 2018.
NASA has faced growing pressure to cut its budget as the US government's debt soars and as the United States buckles under the deepest economic crisis since the Great Depression of the 1930s.
